Commitments and Contingencies (Narratives) (Details) $ in Thousands		3 Months Ended		9 Months Ended
		Aug. 31, 2017 USD ($)	Aug. 31, 2016 USD ($)	Aug. 31, 2017 USD ($) Home	Aug. 31, 2016 USD ($)	Nov. 30, 2016 USD ($)
Loss Contingencies [Line Items]
Excess Insurance Recoveries		$ 23,500
Minimum warranty on electrical and other building systems (in years)				2 years
Maximum warranty on electrical and other building systems (in years)				5 years
Warranty for other components of a home (in years)				1 year
Payments		(6,267)	$ (4,719)	$ (18,836)	$ (17,186)
Adjustment to increase warranty liability		0	0	0	652
Performance bonds		557,500		557,500		$ 535,700
Letters of credit outstanding		33,000		33,000		31,000
Cash deposits		39,133		39,133		42,829
Aggregate purchase price of land		980,184		$ 980,184		1,073,596
Warranty for Other Components of Home				1 year
Loss Contingency, Estimated Recovery from Third Party				$ 11,600
Northern California Townhome Community [Member]
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value				$ 100,000
Damages from Product Defects [Member]
Loss Contingencies [Line Items]
Minimum Number of Affected Homes for Construction Defect Claims | Home				2
Structural warranty provided by the company (in years)				10 years
Warranty Obligations [Member]
Loss Contingencies [Line Items]
Structural warranty provided by the company (in years)				10 years
Self Insurance [Member]
Loss Contingencies [Line Items]
Increase (Decrease) in Insurance Liabilities	[1]	21,700	$ 0	$ 21,700	$ 0
Loss Contingency, Receivable		$ 75,000		$ 75,000		$ 84,500

[1] b)Amounts for the three months and nine months ended August 31, 2017 reflect a change in estimate to increase our self-insurance liability based on a review of actual claim resolution experience, which indicated a higher frequency of claims and, to a lesser extent, a higher claim severity than previously anticipated. Based on these higher historical claim frequency and severity trends, we determined in the 2017 third quarter that future payments for claims relating to homes delivered in certain prior years were likely to exceed the then-estimated liabilities remaining for those claims. Therefore, we recorded an adjustment to increase our self-insurance liability based on an actuarially determined estimate that we believe has a higher probability of being adequate to cover future payments associated with unresolved claims, including claims incurred but not yet reported. This adjustment is included in selling, general and administrative expenses.